QPaintDevice: Must construct a QApplication before a QPaintDevice

[Diez B. Roggisch]

> 
> Yes that I can deduce, but why I'm asking is why it's different on
> Windows and Linux. Should it not be platform independent?

It should be. I've got no idea why it seems to work on windows but I can say
one thing for sure: that would be an artifact that you shouldn't rely on.
In Qt, you _always_ need a QApplication for anything. So just do as it
requires you to do: first, construct a QApplication. Then things will work.

Diez